DAVID MARK: The former federal environment minister, Peter Garrett, has told the insulation royal commission he wasn't aware of safety risks for workers before the death of the first installer.

Mr Garrett has told the inquiry he had ultimate responsibility for the rollout of the Rudd government's home insulation scheme. But Mr Garrett has said he wasn't informed about the risk of injury for inexperienced workers.

Stephanie Smail reports.

STEPHANIE SMAIL: The families of the four workers who died installing insulation have been waiting to hear from the senior Rudd government politicians who were in charge.

Mitchell Sweeney died installing insulation in Queensland in 2010. His brother, Justin Sweeney, spoke outside the royal commission today.

JUSTIN SWEENEY: It's a long time coming for the family. Obviously Peter Garrett and Kevin Rudd are the key stakeholders in the program, so we're very interested to hear what they knew and what they didn't know.

STEPHANIE SMAIL: The former federal environment minister Peter Garrett told the inquiry he was ultimately responsible for the rollout of the economic stimulus scheme. But Mr Garrett has told counsel assisting the commission, Keith Wilson, he was unaware of potential safety risks for installers before Matthew Fuller's death in October 2009.

PETER GARRETT: And I think up until Matthew Fuller's death it wasn't something which had been specifically or formally brought to my attention.

KEITH WILSON: Do you recall seeking advice from the department about whether the program was performing in such a way that there was no or limited concern about people being injured in carrying out insulation work?

PETER GARRETT: I don't recall specifically seeking advice in written form. Whether it was a matter that was raised directly by me in meetings with officials, and at what time, I can't recall.

STEPHANIE SMAIL: The inquiry has heard industry representative Peter Ruz warned bureaucrats very early in the scheme's development that three workers had died installing insulation in a similar scheme in New Zealand.

But Mr Garrett told Mr Wilson he wasn't informed about that either, until after Matthew Fuller's death.

KEITH WILSON: On the 18th February Mr Ruz had told a meeting that there had been the situation in New Zealand where three people had electrocuted themselves. I can tell you as a matter of fact, on the following day, Mr Ruz sent an email to Ms Riordan in the department expanding on that.

On the 3rd of April, the Technical Advisory Grou, advised, as we saw, that there was a risk or high risk of death or catastrophic injury. Surely you must agree that these are matters that should have been brought to your attention?

PETER GARRETT: Yes I do. And I think it's indicative of the fact that the briefs that came to me did not necessarily contain either advices or information, or even reports, if you like, of this kind sufficient to make me believe that we needed to address issues around program design or program delivery.

STEPHANIE SMAIL: The inquiry heard Peter Garrett relied heavily on briefs by department staff and his policy advisers for information about the details of the scheme. He told Keith Wilson he didn't see the risk assessment for the home insulation scheme until it was dumped in February 2010.

KEITH WILSON: I would have expected you to ask for a copy of the risk management plan and the risk register straight after Mr Fuller's death. I'm just wondering why you didn't see it until the 11th February 2010?

PETER GARRETT: My inquiries subsequent to Mr Fuller's death were to the extent of understanding what we additionally needed to do and what matters we ought to address in the future. And that wasn't a matter that specifically came up for discussion at that point in time.

STEPHANIE SMAIL: Peter Garrett told the inquiry the Commonwealth government moved to reduce risks as the program continued by increasing regulations and improving audit and compliance practices. His evidence continues.